[PATCH v6 00/13] introduce the Xen PV Calls frontend

[Stefano Stabellini]

Hi all,

this series introduces the frontend for the newly introduced PV Calls
procotol.

PV Calls is a paravirtualized protocol that allows the implementation of
a set of POSIX functions in a different domain. The PV Calls frontend
sends POSIX function calls to the backend, which implements them and
returns a value to the frontend and acts on the function call.

For more information about PV Calls, please read:

https://xenbits.xen.org/docs/unstable/misc/pvcalls.html

This patch series only implements the frontend driver. It doesn't
attempt to redirect POSIX calls to it. The functions exported in
pvcalls-front.h are meant to be used for that. A separate patch series
will be sent to use them and hook them into the system.


Changes in v6:
- rename PVCALLS_NR_REQ_PER_RING to PVCALLS_NR_RSP_PER_RING
- remove spin_lock/unlock around list_del_init in pvcalls_front_remove
- change list_del_init into list_del in pvcalls_front_remove,
  pvcalls_front_free_map and pvcalls_front_release
- add reviwed-bys
- return EOPNOTSUPP when functions are unimplemented in pvcalls-front
- return ret on error in pvcalls_front_accept
- return an error from __write_ring if size >= array_size
- return 0 instead of -EAGAIN from pvcalls_front_recvmsg when nothing
  was read
- add bool locked parameter to pvcalls_front_free_map
- move "kfree(map)" to pvcalls_front_free_map
- remove socketpass_mappings, now unused


Stefano Stabellini (13):
      xen/pvcalls: introduce the pvcalls xenbus frontend
      xen/pvcalls: implement frontend disconnect
      xen/pvcalls: connect to the backend
      xen/pvcalls: implement socket command and handle events
      xen/pvcalls: implement connect command
      xen/pvcalls: implement bind command
      xen/pvcalls: implement listen command
      xen/pvcalls: implement accept command
      xen/pvcalls: implement sendmsg
      xen/pvcalls: implement recvmsg
      xen/pvcalls: implement poll command
      xen/pvcalls: implement release command
      xen: introduce a Kconfig option to enable the pvcalls frontend

 drivers/xen/Kconfig         |    9 +
 drivers/xen/Makefile        |    1 +
 drivers/xen/pvcalls-front.c | 1273 +++++++++++++++++++++++++++++++++++++++++++
 drivers/xen/pvcalls-front.h |   28 +
 4 files changed, 1311 insertions(+)
 create mode 100644 drivers/xen/pvcalls-front.c
 create mode 100644 drivers/xen/pvcalls-front.h